A daring U.S. military operation in Libya has captured one of America's most-wanted terrorists. The FBI had offered a $5 million reward for the man who's accused of plotting the 1998 Africa embassy bombings. Authorities are now holding him on board a U.S. Navy vessel, where he's being interrogated by a team specializing in high-value intelligence targets. As NPR's Carrie Johnson reports, that's likely to generate criticism.

CARRIE JOHNSON, BYLINE: For more than a dozen years, the man known as Abu Abas al-Libi roamed freely across Africa and the Middle East despite an indictment for his role in bombing American embassies in Africa. Al-Libi is a longtime member of al-Qaida and, according to Secretary of State John Kerry, a legitimate target under U.S. law.

SECRETARY JOHN KERRY: And he is a legal and an appropriate target for the U.S. military under the authorization of the use of military force passed in September of 2001.

JOHNSON: That authorization approved by Congress soon after the 9/11 attacks covers kill or capture missions against al-Qaida and associated forces. Legal experts say the U.S. is on firm ground to seize al-Libi, so that's the law. But what's more controversial is the policy of detaining him for interrogation on the Navy ship before sending him on to trial in New York. Deborah Pearlstein teaches at Cardozo Law School.

DEBORAH PEARLSTEIN: As a matter of policy, is it a good idea for us to be in the business of seizing people all over the world, in countries that may or may not give their consent and detaining them indefinitely before we pursue criminal prosecution? That's much less clear.

JOHNSON: President Obama banned harsh interrogation of detainees when he took office. But interrogating a suspect like al-Libi for a long time, without giving him access to a lawyer, still makes some advocates uncomfortable. Ryan Goodman writes for the national security blog called Just Security.

RYAN GOODMAN: It seems to me that when we have cases of individuals who are actually being tried by our civil system, you would think that they should be read their rights, especially if they're going to be interrogated without a lawyer and the like.

JOHNSON: Yet there is some precedent for this hybrid model of holding a suspect in military custody for weeks, then sending him into the criminal justice system. Two years ago, the Obama administration did just that with a suspect named Ahmed Warsame. Warsame ultimately waived his rights and pleaded guilty to supporting al-Qaida in Yemen and al-Shabab in Somalia.

Even before that case, the U.S. government moved another detainee charged in the Africa embassy bombings from Guantanamo prison to New York City, where he too was convicted. Bobby Chesney teaches national security law at the University of Texas.

BOBBY CHESNEY: Ultimately even in that case, where there was years of detention before being shifted into the criminal prosecution system, the case was allowed to go forward.

JOHNSON: But Chesney says there is a key difference today. In 2011, no one knew that Ahmed Warsame was on board a Navy vessel for two months. Now the world knows al-Libi's whereabouts.

CHESNEY: If we go more than a few more days, I would imagine that you'll hear from some quarter or another of an attempt to begin some kind of proceeding on his behalf. Now, that doesn't mean that a court is going to immediately get involved, but it does mean that there will be a legal friction that will emerge.

JOHNSON: There's no set timeline for how long al-Libi can stay aboard the USS San Antonio. The more time passes, Chesney says, the more civil liberties groups may agitate. But moving him to New York, where he's been indicted, raises a different set of problems.

CHESNEY: The sooner that he ends up being read Miranda rights and brought into the Bureau of Prisons system for pretrial custody, the more criticism they'll encounter from the right.

JOHNSON: Which puts the Obama administration in a familiar place when it comes to national security, squeezed uncomfortably in the middle. Carrie Johnson, NPR News, Washington. Transcript provided by NPR, Copyright NPR.